If at all possible, I don't watch anything in 4:3. Any widescreen movies converted to 4:3 are absolutely butchered.
But an interesting thing I noticed recently was a movie that had different versions on both sides (The Truth about Charlie). But, rather than the 4:3 or native aspect ratio choice that many movies give; it had choices of 16:9 or native 2.35:1.
I find that the "butchering" is much less severe when going from 2.35:1 down to 16:9 / 1.78:1. But, I chose the 2.35:1 side, to see the movie in it's full glory.
BTW - The movie was less than stellar, except for the presence of Thandie Newton.. She is gorgeous.. which helps improve any action movie (she was the hot spy chick in Mission Impossible 2)
First, if you spent $10,000 on a TV, you really got screwed. I spent $2,000 on my HDTV, and have seen some similar sets on clearance for ~$1,000 after I bought mine.
Second, broadcast digital TV (HDTV) IS widescreen. Outside of prime-time, you still get the 4:3 shows.. And this will probably be the case for the foreseeable future of all the syndicated crap. But, widescreen TV's give a variety of methods for filling the whole screen (though, I still prefer unskewed 4:3, with the vertical letterboxing).
"Windows Longhorn will offer sweeping changes over its predecessors and be the most significant release of Microsoft's desktop operating system since Windows 95"
Isn't this how they describe EVERY iteration of their desktop OS's?
The article goes on to describe a bunch of features that would make little or no difference to most users.
Regardless of what you think of their technology, you have to be amazed that they can get so many people to pay ever-increasing amounts of money to "upgrade" their systems to the latest OS.
- Decent price. It's not a full laptop, it's basically a mobility tool. Don't expect consumers to pay laptop prices.
- Battery Life. Many similar devices are handicapped by their short power duration. Especially for a mobile/wireless device, the ability to run for a reasonable amount of time is key.
- Broad WiFi access. This is outside of their control, but from the design, it appears they are counting on it. If WiFi rolls out as broadly as many think it will, this type of device will do a lot of business.
16:9 CCD - All the existing consumer video cameras have 4:3 CCD's. They must accomplish widescreen by kludging the picture some way. Such as, masking off the top and bottom of the picure (letterbox style) to create a 16:9 image - losing a bunch of resolution in the process.
480p60 - In can do 720p30 (1280x720 progressive, 30 frames/sec). But, it can also do 480p60 (720x480 (DVD resolution) progressive, 60 frames/sec). This 60fps capture is great for fast moving action, like sports. (Note that many DVD's are progressive - but only after re-combining the video encoded into 2 interlaced frames. So, it's 480p30. So, this 480p60 would be better than DVD)
Component video to HDTV - It includes an adapter cable to input directly to an HDTV for playback. Otherwise, you don't have an easy way to play back in full HD resolutions... DVD's can't handle it. You could use D-VHS if you had the right tools & formats.
What is the process by which this legislation is getting proposed everywhere. I am not real "up" on state politics, and completely ignorant of cooperation between state governments (I didn't think there was any).
Do state senators e-mail each other saying "here's a great opportunity for you to screw your consitituents".
Or, is someone with a vested interest going to reps from each state government, and pleading the need for this (along with some generous campaign donations)?
I have been buying fewer books of this type recently. In the past, a good O'Reilly book was the best way to get on top of a subject. But, with a few google searches, I can find most everything I need about common topics, like MacOS X.
The argument for disconnected access with books is a bit tougher with a 750page book.. Not really a mobile tool.
Several years ago, the "Big Three" US auto makers, Ford, GM, and Chrysler, began promoting their idea of the Automotive Network eXchange (ANX), to cut costs of communications. See http://www.anx.com/ for more info.
The idea is to eliminate expensive leased lines, by aggregating all traffic onto internet connections using IPSec. The ANX was one of the big drivers IPSec's adoption as the VPN standard.
The ANX will eventually connect 10,000+ automotive supplier companies. Many of these 10,000 are also in Michigan, but the extend all over the world.
Outside of this project, you'll find VPN projects in a high percentage of corporations around the world. The cost savings of using cheap/ubiquitous Internet connections is very compelling. Using VPN's is the only way these companies can do it securely.. this is not going away. I would love for the legislators to persist in these plans, and see how fast they get bitch slapped, setting a cautionary example for future efforts.
I don't know about divx.. the thing that is very interesting to me is the network port. So, I can theoretically access my Linux file server, which has my MiniDV movies, exported to DVD VOB format. Also, as part of my creation process, I can watch them over the network, rather than burning DVD's as tests. And, once I'm done, I can have an easily accessed home movie archive via the network server.
It could also access my MP3 library on that Linux file server.. Could be a nice, small, quiet media server to replace most of my HTPC (Home Theater PC) functionality (everything except the HDTV receiver/recorder).
Advice from my extensive experience in this area
on
Family Tech Support
·
· Score: 4, Insightful
- Ghost is your friend: Before sending them the system, get it working right, then create a ghost image. Burn it on a CD, and have them put it in a safe place. When they screw it up beyond repair, walk them through the process of repaving their system.
- Knoppix: Those hard drives only last so long.. Once that puppy fails, they're offline for a while. A great disaster recovery method is a Knoppix Linux Live-CD. It pops them into a nice X-Windows interface, with all the expected app's, including office apps and Mozilla. This will get them back up and reading e-mail, bidding on EBay, and all those other important tasks. Maybe they'll even convert to Linux.
- VNC: Don't even try to have your dad explain what he sees on the screen (reading for 5 minutes, then skipping over the important error messages). Just connect remotely & poke around for yourself. This becomes a bit more difficult when both sides are on DSL, behind firewalls.. configure port forwarding on your firewall (or use a linux box as a firewall & do VNC on it).
- Use NT/Win2K: Win98 seems to attract all the garbage that can be thrown at it, and not hold up well. Win2K is much more resilient.
- Use NTFS: It may be harder to debug, but it holds up much better to the power-off's and resets that it will inevitably get.
These look very interesting.. The large address space and native bignum math are nice, but not a big deal for me.. I really like the flat address space and increased number of general purpose registers.
This is sort of odd, since those two things are completely abstracted to me when programming in user space.
I was educated on processor architecture and assembly language on the Motorola 68000 processor. So, I have always found the x86 kludgery distasteful. The x86-64 gets rid of two of the major points of the x86 crap, and it feels like a decent architecture.
Now, how about a big-endian x86-64? That would be perfect!
Can you post pointers to any firewire enabled DVD players? I have not seen any.. particularly from Mitsubishi, who you would think would be first in line with a product like this..
There are the upcoming DVD-Audio over firewire products. But, will those support video over firewire? Or, will they be like the current DVD-Audio players, which have SPDIF connectors, but are not allowed to do DVD-A over them.
I would love to have a firewire based home theater. There are so many cool things that could be done. But, like several other areas, political problems slow it down.
Mitsubishi is the biggest proponent of this. It's a great concept, simple wiring (audio/video over the one cable, daisy chained, no need to hub), simple control via the TV's GUI, complete integration.
You can actually use it for a few things. Their integrated HDTV tuner can play/record off of the Mitsubishi or JVC D-VHS VCR via firewire.
But, none of the other major components support firewire.. Not because of any technical limitation, but because of legal/political roadblocks.
- DVD players are forbidden from using digital outputs by all the CSS licensing garbage. So, you cannot by a DVD player to integrate into this system.
- HDTV Satellite systems (or even plain SDTV) do not support firewire. It's not clear if it's DirecTV/Dish not allowing this, or if they are pressured by the MPAA. But, you cannot buy a Sat receiver with firewire today. (There are rumors of both Dish and DirecTV coming out with them this year, with 5C copy protection baked into it).
So, in theory this is a great technology, with limitless potential. In reality, it's very limited.
They send out MILLIONS of CD's already.. I haven't looked at the contents lately, but I assume there would be some free space. Stick a few cool Free Software packages on there as a nice little "fuck you" to microsoft, and also a benefit to the citizenry, to offset the annoyance of the spam-CD.
They really missed the boat on this one. They need some real SMP video action.. Our friends at 3Dfx pioneered this with the Voodoo2, operating in SLI (Scan Line Interlace) mode. Two PCI cards, connected via a jumper cable, each handling half the scan lines for the display.. SMP at it's best!
http://www.hwupgrade.com/skvideo/voodoo2_sli.htm l
I would really like to see this aggressive power management available for non-laptop boards.
I currently use a VIA C3 running at 800MHz for my Linux server doing a bunch of tasks ( firewall, VPN, WWW, SMTP, FTP, NTP, Samba, NFS, MySQL/PHP, Answering Machine, etc.). The C3 is about as fast as a Celeron 500MHz. But, it uses very little power and runs cool enough to use only a passive heat sink. With a quiet Seagate Barracuda hard drive, and a quiet power supply fan, the system is nearly silent - which is great in my small apartment.
I would like to be able to use a processor that idled down 90% of the time when it was doing very little. For those few tasks that need CPU horsepower, it could go up to it's 1.6GHz potential, and turn on cooling fans if needed.
Power / Heat / Noise savings apply to the desktop too!
This looks like a great board.. Integrated USB 2.0 and Firewire are great, especially with only one PCI slot to work with. But, how about a case to put it in?
There are several good options for Mini-ITX motherboards.. If you don't need a lot of CPU power, the VIA EPIA motherboards - with the C3 processor - are a good option. They are low heat, which will help if you can find a small case.
But, this P4 system could be quite challenging, given it's high power and heat dissipation requirements. Anyone have some good suggestions for a case for this thing?
It covers the basics, such as: Bandwidth: Up to 134Mbps Hub Radius: A few kilometers Line of sight propogation
¥ Compared to a Wireless LAN: --Multimedia QoS, not only contention-based --Many more users Many more users --Much higher data rates Much higher data rates --Much longer Much longer distances
802.16 MAC: Overview ¥ Point-to-Multipoint Point-to-Multipoint ¥ Metropolitan Area Network Metropolitan Area Network ¥ Connection-oriented Connection-oriented ¥ Supports difficult user environments Supports difficult user environments --High bandwidth, hundreds of users per channel --Continuous and burst traffic --Very efficient use of spectrum ¥ Protocol-Independent core (ATM, IP, Ethernet, ) ¥ Balances between stability of Balances between stability of contentionless contentionless and efficiency of contention-based operation ¥ Flexible QoS offerings Flexible QoS offerings --CBR, CBR, rt rt-VBR, -VBR, nrt nrt-VBR, BE, with granularity within classes ¥ Supports multiple 802.16
If you can find a TV capture card with decent drivers that allow more than one card to co-exist in a device, you're half way there.
For analog TV, you will need cards with hardware encoders, so all the heavy lifting is offloaded to a specialized chip - away from the CPU, on the other side of the PCI bus (i.e. not effecting either of those resources with high bandwidth requirements).
For digital TV, it's even easier. When the decoder captures the ATSC stream, it is a compressed ~19Mbps MPEG2 stream. The CPU just has to do a few DMA transfers to pull the stream & send it to disk. This is very low overhead. I have an HDTV PCI card today, when capturing, it's barely a blip on the CPU meter.
The PCI bus is irrelevant at this point, because it could theoretically handle over 20 of these ATSC streams simultaneously (32 bit / 33 Mhz PCI is ~1Gbps). If you think you need more headroom, go with a server board, with 3 peer PCI-X busses, they are not expensive.
The Hard drive performance should also be a non-factor. Hard drives are rated in MegaBytes per second (a decent one is ~40MB/s). So, you can fit plenty of 20 MegaBIT/s streams into that pipe.
Hard drive capacity is a bigger issue.. Slap in a few 200-250GB disks in a RAID array, and you're all set.
Unfortunately not... There are currently NO vendors that support Linux drivers for their PCI HD PCI cards. In fact, they won't even release their spec's so people can independently make Linux drivers.
I have e-mailed the card vendors directly, and they defer to Teralogic, who created the card design and licensed the original drivers. Teralogic has been unresponsive to many requests for Linux driver or hardware specs.
Actually, there are several HDTV PCI cards you can put in a Windows PC to decode/record/display Off The Air HDTV. These take about 9GB/hr for HDTV content.
Both Off The Air and Satellite HDTV programs use MPEG2 compression.
All HDTV is pre-compressed as an MPEG2 data stream. The "Off The Air" HDTV broadcasts are 19.3Mbps, and the satellites are usually in the same ballpark (they can do higher bit rates, but from what I have heard it is often ~15Mbps).
The Tivo will just copy the transport stream to the hard drive, the same way a DirecTivo does today. No loss in quality, and very low CPU requirements.
All of the current field of cards is based on the Janus reference design, by Teralogic. So, they are all very similar.
They all take a standard antenna as input (cheap UHF antennas, like the Radio Shack double bowtie work great). They have onboard ATSC Digital TV tuners, which decode the 19.3Mbps data channel containing MPEG2 video Digital audio (some channels support Dolby Digital 5.1 audio). They have onboard MPEG2 hardware decoders which output the HDTV programs in their high resolution formats (1080i: 1920x1080 interlaced or 720p: 1280x720 progressive). They output through a VGA/RGB port, though some support transcoding to component video out. They can also output on the PC desktop in a small scaled down video window.
The Players:
- Telemann HiPix DTV-200 - http://www.telemann.com/products/dtv200.html - Probably the most popular, has been around for a long time, but seems to be abandoned by Telemann. There is some driver source code availability (not open source, but available to the community under restricted terms) and people at avsforum.com have made large contributions. Availability of the card is pretty spotty, and ongoing support is very questionable.
- AccessDTV - http://www.accessdtv.com/accessdtv/index.htm - Card has some additional hardware, which enables some Tivo-like features, such as pausing live tv with the view buffer. Initially this card was unpopular because they felt the need to encrypt their data files, eliminating the possibility of sharing between PC's or even editing files. Recent versions of their software have relented on this encryption stance, so this could be a good card.
- MIT MDP-100 ( the "MyHD" card ) - http://www.mitinc.co.kr/e_pccard.htm - $300 - Has two antenna inputs, handy for positioning seperate antennas to get all stations. Also includes the ability to play back DVD's at 480P or non-CCS VOB files at HDTV resolutions, which is a great feature for a home theater.. DVD's look great scaled to 720P. Drivers are still immature and can be unstable, but not bad for normal usage.
- Digital STREAM HiDTV Pro HDTV - http://www.pc-dtv.com/ - $370 - Relatively new card, very similar to others, software looks more polished than some others.
- Happauge WinTV-HD - http://www.hauppauge.com/html/products.htm - Poor drivers, no recording capability. Product appears to be abandoned, no driver updates. Stay away from this card.
- Happauge WinTV-D - http://www.hauppauge.com/html/products.htm - Similar to the above card, except it only displays at 480i on the desktop (it scales all hi-res HDTV down to standard TV resolutions). This card may be okay if you ONLY want to watch digital TV on your PC desktop in a little window. If you want to watch on an HDTV, stay away from this card.
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If at all possible, I don't watch anything in 4:3. Any widescreen movies converted to 4:3 are absolutely butchered.
But an interesting thing I noticed recently was a movie that had different versions on both sides (The Truth about Charlie). But, rather than the 4:3 or native aspect ratio choice that many movies give; it had choices of 16:9 or native 2.35:1.
I find that the "butchering" is much less severe when going from 2.35:1 down to 16:9 / 1.78:1. But, I chose the 2.35:1 side, to see the movie in it's full glory.
BTW - The movie was less than stellar, except for the presence of Thandie Newton.. She is gorgeous.. which helps improve any action movie (she was the hot spy chick in Mission Impossible 2)
Screw Blockbuster. Go with Netflix. They seem to use exclusively widescreen (unless it's not available for a certain movie).
First, if you spent $10,000 on a TV, you really got screwed. I spent $2,000 on my HDTV, and have seen some similar sets on clearance for ~$1,000 after I bought mine.
Second, broadcast digital TV (HDTV) IS widescreen. Outside of prime-time, you still get the 4:3 shows.. And this will probably be the case for the foreseeable future of all the syndicated crap. But, widescreen TV's give a variety of methods for filling the whole screen (though, I still prefer unskewed 4:3, with the vertical letterboxing).
"Windows Longhorn will offer sweeping changes over its predecessors and be the most significant release of Microsoft's desktop operating system since Windows 95"
Isn't this how they describe EVERY iteration of their desktop OS's?
The article goes on to describe a bunch of features that would make little or no difference to most users.
Regardless of what you think of their technology, you have to be amazed that they can get so many people to pay ever-increasing amounts of money to "upgrade" their systems to the latest OS.
- Decent price. It's not a full laptop, it's basically a mobility tool. Don't expect consumers to pay laptop prices.
- Battery Life. Many similar devices are handicapped by their short power duration. Especially for a mobile/wireless device, the ability to run for a reasonable amount of time is key.
- Broad WiFi access. This is outside of their control, but from the design, it appears they are counting on it. If WiFi rolls out as broadly as many think it will, this type of device will do a lot of business.
16:9 CCD - All the existing consumer video cameras have 4:3 CCD's. They must accomplish widescreen by kludging the picture some way. Such as, masking off the top and bottom of the picure (letterbox style) to create a 16:9 image - losing a bunch of resolution in the process.
480p60 - In can do 720p30 (1280x720 progressive, 30 frames/sec). But, it can also do 480p60 (720x480 (DVD resolution) progressive, 60 frames/sec). This 60fps capture is great for fast moving action, like sports. (Note that many DVD's are progressive - but only after re-combining the video encoded into 2 interlaced frames. So, it's 480p30. So, this 480p60 would be better than DVD)
Component video to HDTV - It includes an adapter cable to input directly to an HDTV for playback. Otherwise, you don't have an easy way to play back in full HD resolutions... DVD's can't handle it. You could use D-VHS if you had the right tools & formats.
What is the process by which this legislation is getting proposed everywhere. I am not real "up" on state politics, and completely ignorant of cooperation between state governments (I didn't think there was any).
Do state senators e-mail each other saying "here's a great opportunity for you to screw your consitituents".
Or, is someone with a vested interest going to reps from each state government, and pleading the need for this (along with some generous campaign donations)?
Can anyone shed some light on this?
I have been buying fewer books of this type recently. In the past, a good O'Reilly book was the best way to get on top of a subject. But, with a few google searches, I can find most everything I need about common topics, like MacOS X.
The argument for disconnected access with books is a bit tougher with a 750page book.. Not really a mobile tool.
Several years ago, the "Big Three" US auto makers, Ford, GM, and Chrysler, began promoting their idea of the Automotive Network eXchange (ANX), to cut costs of communications. See http://www.anx.com/ for more info.
The idea is to eliminate expensive leased lines, by aggregating all traffic onto internet connections using IPSec. The ANX was one of the big drivers IPSec's adoption as the VPN standard.
The ANX will eventually connect 10,000+ automotive supplier companies. Many of these 10,000 are also in Michigan, but the extend all over the world.
Outside of this project, you'll find VPN projects in a high percentage of corporations around the world. The cost savings of using cheap/ubiquitous Internet connections is very compelling. Using VPN's is the only way these companies can do it securely.. this is not going away. I would love for the legislators to persist in these plans, and see how fast they get bitch slapped, setting a cautionary example for future efforts.
I don't know about divx.. the thing that is very interesting to me is the network port. So, I can theoretically access my Linux file server, which has my MiniDV movies, exported to DVD VOB format. Also, as part of my creation process, I can watch them over the network, rather than burning DVD's as tests. And, once I'm done, I can have an easily accessed home movie archive via the network server.
It could also access my MP3 library on that Linux file server.. Could be a nice, small, quiet media server to replace most of my HTPC (Home Theater PC) functionality (everything except the HDTV receiver/recorder).
- Ghost is your friend: Before sending them the system, get it working right, then create a ghost image. Burn it on a CD, and have them put it in a safe place. When they screw it up beyond repair, walk them through the process of repaving their system.
- Knoppix: Those hard drives only last so long.. Once that puppy fails, they're offline for a while. A great disaster recovery method is a Knoppix Linux Live-CD. It pops them into a nice X-Windows interface, with all the expected app's, including office apps and Mozilla. This will get them back up and reading e-mail, bidding on EBay, and all those other important tasks. Maybe they'll even convert to Linux.
- VNC: Don't even try to have your dad explain what he sees on the screen (reading for 5 minutes, then skipping over the important error messages). Just connect remotely & poke around for yourself. This becomes a bit more difficult when both sides are on DSL, behind firewalls.. configure port forwarding on your firewall (or use a linux box as a firewall & do VNC on it).
- Use NT/Win2K: Win98 seems to attract all the garbage that can be thrown at it, and not hold up well. Win2K is much more resilient.
- Use NTFS: It may be harder to debug, but it holds up much better to the power-off's and resets that it will inevitably get.
These look very interesting.. The large address space and native bignum math are nice, but not a big deal for me.. I really like the flat address space and increased number of general purpose registers.
This is sort of odd, since those two things are completely abstracted to me when programming in user space.
I was educated on processor architecture and assembly language on the Motorola 68000 processor. So, I have always found the x86 kludgery distasteful. The x86-64 gets rid of two of the major points of the x86 crap, and it feels like a decent architecture.
Now, how about a big-endian x86-64? That would be perfect!
Google comes up with this link that says Texas was derived from the Hasinai Indian word "tejas", which means friend.
Can you post pointers to any firewire enabled DVD players? I have not seen any.. particularly from Mitsubishi, who you would think would be first in line with a product like this..
There are the upcoming DVD-Audio over firewire products. But, will those support video over firewire? Or, will they be like the current DVD-Audio players, which have SPDIF connectors, but are not allowed to do DVD-A over them.
I would love to have a firewire based home theater. There are so many cool things that could be done. But, like several other areas, political problems slow it down.
Mitsubishi is the biggest proponent of this. It's a great concept, simple wiring (audio/video over the one cable, daisy chained, no need to hub), simple control via the TV's GUI, complete integration.
You can actually use it for a few things. Their integrated HDTV tuner can play/record off of the Mitsubishi or JVC D-VHS VCR via firewire.
But, none of the other major components support firewire.. Not because of any technical limitation, but because of legal/political roadblocks.
- DVD players are forbidden from using digital outputs by all the CSS licensing garbage. So, you cannot by a DVD player to integrate into this system.
- HDTV Satellite systems (or even plain SDTV) do not support firewire. It's not clear if it's DirecTV/Dish not allowing this, or if they are pressured by the MPAA. But, you cannot buy a Sat receiver with firewire today. (There are rumors of both Dish and DirecTV coming out with them this year, with 5C copy protection baked into it).
So, in theory this is a great technology, with limitless potential. In reality, it's very limited.
They send out MILLIONS of CD's already.. I haven't looked at the contents lately, but I assume there would be some free space. Stick a few cool Free Software packages on there as a nice little "fuck you" to microsoft, and also a benefit to the citizenry, to offset the annoyance of the spam-CD.
They really missed the boat on this one. They need some real SMP video action.. Our friends at 3Dfx pioneered this with the Voodoo2, operating in SLI (Scan Line Interlace) mode. Two PCI cards, connected via a jumper cable, each handling half the scan lines for the display.. SMP at it's best!
m l
http://www.hwupgrade.com/skvideo/voodoo2_sli.ht
I would really like to see this aggressive power management available for non-laptop boards.
I currently use a VIA C3 running at 800MHz for my Linux server doing a bunch of tasks ( firewall, VPN, WWW, SMTP, FTP, NTP, Samba, NFS, MySQL/PHP, Answering Machine, etc.). The C3 is about as fast as a Celeron 500MHz. But, it uses very little power and runs cool enough to use only a passive heat sink. With a quiet Seagate Barracuda hard drive, and a quiet power supply fan, the system is nearly silent - which is great in my small apartment.
I would like to be able to use a processor that idled down 90% of the time when it was doing very little. For those few tasks that need CPU horsepower, it could go up to it's 1.6GHz potential, and turn on cooling fans if needed.
Power / Heat / Noise savings apply to the desktop too!
This looks like a great board.. Integrated USB 2.0 and Firewire are great, especially with only one PCI slot to work with. But, how about a case to put it in?
There are several good options for Mini-ITX motherboards.. If you don't need a lot of CPU power, the VIA EPIA motherboards - with the C3 processor - are a good option. They are low heat, which will help if you can find a small case.
But, this P4 system could be quite challenging, given it's high power and heat dissipation requirements. Anyone have some good suggestions for a case for this thing?
On the IEEE page there is a good overview document (zipped PDF).
It covers the basics, such as:
Bandwidth: Up to 134Mbps
Hub Radius: A few kilometers
Line of sight propogation
¥ Compared to a Wireless LAN:
--Multimedia QoS, not only contention-based
--Many more users Many more users
--Much higher data rates Much higher data rates
--Much longer Much longer distances
802.16 MAC: Overview
¥ Point-to-Multipoint Point-to-Multipoint
¥ Metropolitan Area Network Metropolitan Area Network
¥ Connection-oriented Connection-oriented
¥ Supports difficult user environments Supports difficult user environments
--High bandwidth, hundreds of users per channel
--Continuous and burst traffic
--Very efficient use of spectrum
¥ Protocol-Independent core (ATM, IP, Ethernet, ) ¥ Balances between stability of Balances between stability of contentionless contentionless and
efficiency of contention-based operation
¥ Flexible QoS offerings Flexible QoS offerings
--CBR, CBR, rt rt-VBR, -VBR, nrt nrt-VBR, BE, with granularity within classes
¥ Supports multiple 802.16
If you can find a TV capture card with decent drivers that allow more than one card to co-exist in a device, you're half way there.
For analog TV, you will need cards with hardware encoders, so all the heavy lifting is offloaded to a specialized chip - away from the CPU, on the other side of the PCI bus (i.e. not effecting either of those resources with high bandwidth requirements).
For digital TV, it's even easier. When the decoder captures the ATSC stream, it is a compressed ~19Mbps MPEG2 stream. The CPU just has to do a few DMA transfers to pull the stream & send it to disk. This is very low overhead. I have an HDTV PCI card today, when capturing, it's barely a blip on the CPU meter.
The PCI bus is irrelevant at this point, because it could theoretically handle over 20 of these ATSC streams simultaneously (32 bit / 33 Mhz PCI is ~1Gbps). If you think you need more headroom, go with a server board, with 3 peer PCI-X busses, they are not expensive.
The Hard drive performance should also be a non-factor. Hard drives are rated in MegaBytes per second (a decent one is ~40MB/s). So, you can fit plenty of 20 MegaBIT/s streams into that pipe.
Hard drive capacity is a bigger issue.. Slap in a few 200-250GB disks in a RAID array, and you're all set.
Unfortunately not... There are currently NO vendors that support Linux drivers for their PCI HD PCI cards. In fact, they won't even release their spec's so people can independently make Linux drivers.
I have e-mailed the card vendors directly, and they defer to Teralogic, who created the card design and licensed the original drivers. Teralogic has been unresponsive to many requests for Linux driver or hardware specs.
Actually, there are several HDTV PCI cards you can put in a Windows PC to decode/record/display Off The Air HDTV. These take about 9GB/hr for HDTV content.
Both Off The Air and Satellite HDTV programs use MPEG2 compression.
All HDTV is pre-compressed as an MPEG2 data stream. The "Off The Air" HDTV broadcasts are 19.3Mbps, and the satellites are usually in the same ballpark (they can do higher bit rates, but from what I have heard it is often ~15Mbps).
The Tivo will just copy the transport stream to the hard drive, the same way a DirecTivo does today. No loss in quality, and very low CPU requirements.
Here is the situation on with HDTV PCI cards..
All of the current field of cards is based on the Janus reference design, by Teralogic. So, they are all very similar.
They all take a standard antenna as input (cheap UHF antennas, like the Radio Shack double bowtie work great). They have onboard ATSC Digital TV tuners, which decode the 19.3Mbps data channel containing MPEG2 video Digital audio (some channels support Dolby Digital 5.1 audio). They have onboard MPEG2 hardware decoders which output the HDTV programs in their high resolution formats (1080i: 1920x1080 interlaced or 720p: 1280x720 progressive). They output through a VGA/RGB port, though some support transcoding to component video out. They can also output on the PC desktop in a small scaled down video window.
The Players:
- Telemann HiPix DTV-200 - http://www.telemann.com/products/dtv200.html - Probably the most popular, has been around for a long time, but seems to be abandoned by Telemann. There is some driver source code availability (not open source, but available to the community under restricted terms) and people at avsforum.com have made large contributions. Availability of the card is pretty spotty, and ongoing support is very questionable.
- AccessDTV - http://www.accessdtv.com/accessdtv/index.htm - Card has some additional hardware, which enables some Tivo-like features, such as pausing live tv with the view buffer. Initially this card was unpopular because they felt the need to encrypt their data files, eliminating the possibility of sharing between PC's or even editing files. Recent versions of their software have relented on this encryption stance, so this could be a good card.
- MIT MDP-100 ( the "MyHD" card ) - http://www.mitinc.co.kr/e_pccard.htm - $300 - Has two antenna inputs, handy for positioning seperate antennas to get all stations. Also includes the ability to play back DVD's at 480P or non-CCS VOB files at HDTV resolutions, which is a great feature for a home theater.. DVD's look great scaled to 720P. Drivers are still immature and can be unstable, but not bad for normal usage.
- Digital STREAM HiDTV Pro HDTV - http://www.pc-dtv.com/ - $370 - Relatively new card, very similar to others, software looks more polished than some others.
- Happauge WinTV-HD - http://www.hauppauge.com/html/products.htm - Poor drivers, no recording capability. Product appears to be abandoned, no driver updates. Stay away from this card.
- Happauge WinTV-D - http://www.hauppauge.com/html/products.htm - Similar to the above card, except it only displays at 480i on the desktop (it scales all hi-res HDTV down to standard TV resolutions). This card may be okay if you ONLY want to watch digital TV on your PC desktop in a little window. If you want to watch on an HDTV, stay away from this card.